An early cyclone method and apparatus is known from U.S. Pat No. 453,105 (Bretney), issued May 26, 1891, in which there are two stages, in line, in the separating cyclone. A frequent problem with this and later cyclone devices is that efficiency of separation is markedly decreased after either capacity or feed solids concentration are increased. Later cyclone designs eliminated the small in-line second stage cyclone, but introduced only slight construction changes, not changing, however, the general principle of cyclone operation and not eliminating those disadvantages.
A cyclone is a device that creates a vortex that does the work of separating the particulate matter from the fluid. In all present uses of the cyclone, this vortex is short, so that, the time when the particles are subjected to centrifugal separation forces, the so called residence time, is short also.
The advantages of creating a cyclone air core were discovered and afterwards used to greatly improve the cyclone collector (Wlodzimierz J. Tuszko et al. U.S. Pat. No. 4,927,298 issued May 22, 1990; U.S. Pat. No. 5,071,542 issued Dec. 10, 1991, U.S. Pat. No. 5,273,647, issued Dec. 28, 1993, filed Dec. 13, 1991. U.S. Pat. No. 5,269,949, issued Dec. 14, 1993.
It is therefore one object of the present invention to increase the residence time of a cyclone separator at least threefold.
A further object of the present invention is to increase the feed capacity of a conventional cyclone separator at least 1.7 times.
Another object of the present invention is to provide the same cyclone pressure drop and energy consumption as are typically provided in conventional cyclone separators.
Still another object of the invention is to provide an apparatus for centrifugal separations of fluids.